John h



@niet JOHN H. TRUEX, OF ROO-BESTER, NEWYORK.

Letters Pate-.fa No. 110,696, einen January isn'.

IMPROVEMENT iN PLATFORM-SCALES.

The Schedule referred te in these Letters Patent and making of the same.

To all whom it may concern.:

Beit known that I, JOHN H. TRUEX, of the city of tochester, in thecounty of Monroe and State of New York, have invented a certain new andnseiul Improvement in Platform-Scales, of which the following is aspecification.

Nature of the Invention.

This invention is similar in principle to the patent of ThaddeusFairbanks, December' 2i), 1859, but cmbodies an improved constructionand arrangement ci' the parts, whereby the levers and their stir-rupshave a free and independent action.

General Descrip tion In the drawing- Figure l is a perspective view ofmy improvement.

Figure 2,a vertical cross-section of' the saine, shov'. ing the free andindependent action oi the levers and their stirrups.

Figure 3, a view of Fairbanks scale.

A A represent the levers;

B B, the stirrups; and

O represents the loop by which the parts are suspended.

The leversare of the kind ordinarily used, and at their outer o1'divergngl ends are attached to the opposite corners ofthe platform.

At their inner or converging ends they have bearing-points c a, whichrest respectively in bearings l; i in the bottom bars of the stirrups.

The stirrups are simply rectangul-ar i'raiues, resting` one within theother, and being entirely free., and having no connection one with theother, except the passage of the sides of the loop C, through the holes(l d ofthe outer one. y

v These holes are made somewhat larger than the sides of the loop, so asto allow a free actinof the inner1 in the outer stirrup.

The top bar of the inner stirrup also has a bearingpoint, f, upon whichrests and is suspended the outer stirrup.

The advantage of this construction is as follows:

` Each lever and its stirrup has a free action, so that it can swingoutward or inward independently ot" the other, as shown by the outlinein fig. 2. In other words, yas the outer stirrup is simply hung upon thebearing-point f, and as its lever, resting upon its lower bar, isentirely free 'ofany attachment to or connection with the other stirrupand lever, said parts can be thrown out oi' in without, in any manner,affecting the other parts.

This action is very necessary, since it is frequently the case thatheavy weights are dropped heavily upon one side or the other oi' theplatform, which give-s a sudden impetus and causes binding and rigidityunless son/ie provision is made tc relieve it. In this arrangenient, theindependent action of each set of levers and sth-rups, obviates alldicnlty of the kind.

In Fairbanks scale this effect cannot bc accomplished, since the upperbar ci' the'outer stirrup, and the lower bar of the inner stirrnp, bothbear and bind upon the double points it it of the upper lever, which arethus confined between them.

It will-be seen that if either this or the lower lever receives an endmotion, it must impart the saine motion to both stirrups, instead ofone, and consequently to the other lever. Therefore, both sets of leversand stirrnps are practically bound together, which renders them stiliand rigid in action, and not so eil Vective in use.

In addition to the above, there is an essential difference inthe'construction of the two devices, since in mine two rectangularframes of complet-e forni are used, one situated within the other, whilcin Fairbanks but one frame is used, with a attached to the loop insideto form the inner one.

I am aware that stir-rups have been suspended one within the other, butthey are only set one upon the other on the pivots, and are notconnected together, which renders the scales liable tobe thrown down byany liar or sudden movement.

In my invention the liability to suoli accidents is avoided by thestirrups being loosely held together by the continuation of the loop O,which passes through thefupper plate of the outside stirrnp, and throughthe sides ot' the inner stirrup, andis secured by a suitable nut.

C latin.

What I claim, and desire to secure by Letters Pa*- ent, is

The arrangement oi' the two stirrups B B', one inside 'of the other, theouter suspended on the inner, both being loosely attached to each otherby the continuation of rthe loop G, which p'revents their being detachedby accident, with the levers A A resting upon their respective stirrupsindependently of any connection with the other, whereby a free actionof'each set is obtained with a secure construction of mechanism, asherein shown and described. y

J. H. TRUEX.

Witnesses:

R. F. Oscoop, G. WILLM. MIATT.

